fix rawkey duplication BUG

I got following error in version 1.1.0.
we never use timestamp in rawkey because rawkey can't duplicate.
i just put guid postfix for rawkey creation rule.


```

00000000-0000-0000-0000-000000000000,2520746523224702558,2012/01/27 7:14:37,00000000-0000-0000-0000-000000000000,Error,"2012/01/27 7:14:37","SyncService [Table => IIS] - Failed to update IIS site information from table storage.

==============================================================================

DataServiceRequestException:An error occurred while processing this request.

   at System.Data.Services.Client.DataServiceContext.SaveResult.HandleBatchResponse()

   at System.Data.Services.Client.DataServiceContext.SaveResult.EndRequest()

   at System.Data.Services.Client.DataServiceContext.SaveChanges(SaveChangesOptions options)

   at Microsoft.Samples.DPE.WebDeployMatrix.Web.Core.Storage.AzureTable`1.AddEntity(IEnumerable`1 objs) in c:\users\administrator\documents\visual studio 2010\Projects\WebDeployMatrix\WebDeployMatrix\WebDeployMatrix.Web\Core\Storage\AzureTable.cs:line 73

   at Microsoft.Samples.DPE.WebDeployMatrix.Web.Core.Diagnostics.AzureTableTraceListener.TraceEventCore(TraceEventCache eventCache, String source, TraceEventType eventType, Int32 id, String message) in c:\users\administrator\documents\visual studio 2010\Projects\WebDeployMatrix\WebDeployMatrix\WebDeployMatrix.Web\Core\Diagnostics\AzureTableTraceListener.cs:line 50

   at Microsoft.Samples.DPE.WebDeployMatrix.Web.Core.Diagnostics.SimplifiedTraceListener.FilterTraceEventCore(TraceEventCache eventCache, String source, TraceEventType eventType, Int32 id, String message) in c:\users\administrator\documents\visual studio 2010\Projects\WebDeployMatrix\WebDeployMatrix\WebDeployMatrix.Web\Core\Diagnostics\SimplifiedTraceListener.cs:line 68

   at System.Diagnostics.TraceSource.TraceEvent(TraceEventType eventType, Int32 id, String format, Object[] args)

   at Microsoft.Samples.DPE.WebDeployMatrix.Web.Core.Diagnostics.TraceHelper.TraceInformation(String format, Object[] args) in c:\users\administrator\documents\visual studio 2010\Projects\WebDeployMatrix\WebDeployMatrix\WebDeployMatrix.Web\Core\Diagnostics\TraceHelper.cs:line 29

   at Microsoft.Samples.DPE.WebDeployMatrix.Web.Core.Services.IISManager.UpdateSites(IEnumerable`1 sites) in c:\users\administrator\documents\visual studio 2010\Projects\WebDeployMatrix\WebDeployMatrix\WebDeployMatrix.Web\Core\Services\IISManager.cs:line 234

   at Microsoft.Samples.DPE.WebDeployMatrix.Web.Core.Services.SyncService.UpdateIISSitesFromTableStorage() in c:\users\administrator\documents\visual studio 2010\Projects\WebDeployMatrix\WebDeployMatrix\WebDeployMatrix.Web\Core\Services\SyncService.cs:line 202

   at Microsoft.Samples.DPE.WebDeployMatrix.Web.Core.Services.SyncService.SyncForever(TimeSpan interval) in c:\users\administrator\documents\visual studio 2010\Projects\WebDeployMatrix\WebDeployMatrix\WebDeployMatrix.Web\Core\Services\SyncService.cs:line 90

==============================================================================



==============================================================================

DataServiceClientException:<?xml version="1.0" encoding="utf-8" standalone="yes"?>

<error xmlns="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata">

  <code>EntityAlreadyExists</code>

  <message xml:lang="en-US">The specified entity already exists.
RequestId:04c11091-0a7d-405c-947a-0c679f84676c
Time:2012-01-27T07:14:37.1976956Z</message>

</error>

   at System.Data.Services.Client.DataServiceContext.SaveResult.<HandleBatchResponse>d__1e.MoveNext()

==============================================================================",WebDeployMatrix.Web_IN_2

```